1. Field of the Invention
The present invention relates to a method of producing a wire-connection structure for performing electrical connections, and the wire-connection structure.
2. Description of the Related Art
A wire-connection structure, in which contact points arranged with an insulating substrate sandwiched therebetween are electrically connected via an electroconductive material filled in through holes formed in the substrate, is available. As a method of producing such a wire-connection structure, for example, in a semiconductor apparatus described in Japanese Patent Application Laid-open No. 2001-250842 (FIG. 4), wirings formed on one surface of an insulating substrate and electrodes of a semiconductor chip arranged on an opposite side with respect to the wiring, sandwiching the substrate therebetween, are electrically connected by filling an electroconductive material in a form of a paste, a liquid, or a gel in through holes formed in the insulating substrate (substrate).
However, when the electroconductive material is filled to block the through holes entirely as in the semiconductor apparatus described in Japanese Patent Application Laid-open No. 2001-250842, air is remained in the through hole between the electrode of a semiconductor chip and the electroconductive material, and there is a fear that a poor (unsatisfactory) connection occurs. Further, when the electroconductive material is filled in the through holes, depending on a condition of a surface defining (forming) the through holes of the substrate, there is also a fear that the electroconductive material is not reached up to the opposite side of the substrate along the surface defining the through holes, thereby causing a poor connection. Other than filling the electroconductive material in the through holes in such a manner, it is also conceivable to electrically connect contact points, arranged to sandwich the substrate therebetween, by making the electroconductive material to flow, at a side wall of the substrate, from one surface of the substrate toward the other surface of the substrate. In this case also, however, depending on the condition of the side wall, there is a fear that the electroconductive material does not reach up to the other surface of the substrate along the side wall in some cases, thereby causing a poor connection.